Door mechanism



Oct.- 7, 1958 F. H. HIEATT 2,854,707

DOOR MECHANISM Filed March 28. 1955 2 Sheets-Sheet 1 max/170e, B .Feezsrfl 150.5477

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Oct. 1958 F. H. HIEATT 2,854,707

, DOOR MECHANISM Filed March 28, 1955 2 Sheets-Sheet 2 'm z: 1% WVMX United States Patent U DOOR MECHANISM Forrest Henry Hieatt, Burbank, Calif., assignor to Hieatt Engineering Co., Burbank, Califi, a corporation of California Application March 28, 1955, Serial No. 497,003

3 Claims. (Cl. 20-19) This invention relates to a door mechanism and is particularly concerned with the opening and closing of large doors of heavy construction, which doors are required to have sealing engagement with the frame of an opening, it being a general object of this invention to provide a simple, inexpensive and effective mechanism for handling such doors.

In the manufacture of chambers, such as, for example, sub-atmospheric or super-atmospheric test chambers, heavy construction is employed and the structure may be of considerable size. In addition to the large size and heavy construction heat insulation is provided in the form of layers of suitable insulating materials. Further, the operation of such structures is materially hampered since extremely low temperatures are reached resulting in icing conditions which prevent proper functioning of ordinary mechanisms. Thus, it will be apparent that a door mechanism of improved construction and adapted to better handle doors of the type under construction is highly desirable.

An object of this invention is to provide a mechanism for reliably handling a door or closure element of heavy construction whereby a simple, rugged support is provided for the door, and a construction that will not be subject to jamming or mal-function due to low temperature icing conditions.

Another object of this invention is to provide a mechanism which eliminates ordinary hinges and locks and which suspends or holds the door or closure in pressure sealing engagement with the frame of a door receiving opening.

It is another object of this invention to provide a door mechanism of the character referred to that moves or shifts the door away from the floor area in front of the chamber in order to avoid encroaching upon or encumbering said area. In ordinary door mechanisms the door is hinged and swings in an are through said area.

It is still another object of this invention to provide a balanced door handling mechanism that is easily operated with a minimum of power, and to provide means for operation or actuation thereof, preferably a fluid operated means.

Further still, it is an object of this invention to provide a simple and effective seal for a door of the character above referred to and to provide a mechanism which operates to break the door away from the seal so that the seal is not adversely affected by motion of the door as the door is operated.

1 The various objects and features of my invention will be fully understood from the following detailed description of a typical preferred form and application of my invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. 1 is a front elevation of the door mechanism of the present invention. Fig 2 is an enlarged sectional view taken as indicated by line 22 on Fig. 1. Fig. 3 is an enlarged detailed sectional view taken as indicated by line 2,854,707 Patented Oct. 7, 1958 3-3 on Fig. 1. Fig. 4 is a side elevation of the structure shown in Fig. 1, being a view taken as indicated by line 44 on Fig. 1, showing the door in the closed position, and Fig. 5 is a view similar to Fig. 4, showing the door in an open position.

Heretofore, it has been common practice to provide testing chambers of the type under consideration with a door or closure carried on hinges and provided with one or more locking devices to hold the door in sealing engagement with the frame of an opening. Such a structure is not altogether satisfactory, since the sealing parts are acted upon unevenly and because misalignment often develops between the door and the frame or the opening. As shown throughout the drawings, there is a typical testing chamber 10 provided with a door or closure 11. In the case illustrated, the chamber 10 is rectangular or box-like in configuration and involves bottom and top walls 12 and 13 and side walls 14. The walls of the chamber 10 are preferably cellular in construction and involve frame members 15 and inner and outer surface plates 16 and 17. The front of the chamber 10 is open and the frame members 15 at the opening form a door receiving frame. The cells between the plates 16 and 17 are filled or occupied by suitable insulating material 18, such as cork or the like.

The door 11 is preferably cellular in construction, like the chamber 10, and involves a frame 20 and inner and outer surface plates 21 and 22. In accordance with the invention the plates 21 and 22 are simple, flat plates, the plate 21 being adapted to have sealing engagement with the front face of the chamber 10 as hereinafter described. The cells between the plates of the door 11 are filled or occupied by suitable insulating material 18, such as cork or the like.

It is to be understood that the chamber 10 and the door 11 may be of any suitable shape and configuration as circumstances require. For example, the chamber 11 may be cylindrical, in which case the door 11 will be round. It is also to be understood that the walls of the chamber and door may be simple Walls of one layer of material and without the insulation 18 above referred to.

The door mechanism of the present invention is provided to open and close the door 11 or, in other words, to remove or apply the door 11 to the open end of the chamber 10 to have sealing engagement therewith. As shown in Figs. 2 and 3 of the drawings, the frame 15 of the chamber 10 presents a fiat door engaging face 24 that receives the flat inner plate 21 of the door 11. The mechanism that I have provided involves, generally, a support 'A, a door carrying means B, a door guiding means C, a door operating means D, and a door balancing means E. The support A is provided to carry the other elements of the structure, the door carrying means B, the door guiding means C, and the door operating means D being carried thereby in proper operative relationship. The door balancing means E is supported by and cooperates with the door carrying means B as hereinafter described.

The support A is provided to carry the other elements of the mechanism and is preferably a frame-like structure supported on a foundation or by the frame 15 of the chamber 10 to occur at or surrounding the open end of the chamber. As shown, the support A involves vertically disposed side members 25, one at each side of the chamber 11), a horizontally disposed header 26 extending between and joining the upper ends of the members 25 and horizontally disposed rearwardly extending members 27 and suitable braces 28. The side members 25 are provided to support thedoor guiding means C, the header 26 is provided to support the door carrying means B, and the members 27 and braces 28 are provided to brace the frame A and to support the door operating means D.

The door balancing means E is supported by the door carrying means B to operate therewith. It will be readily understood that the specificdesign or construction of the frame A may vary as circumstances require.

Sealing means is provided between the chamber wand door 11, or between the flat door engaging face 24 of the chamber and the flat plate 21, of the door 11. Various types of sealsmay be employed. I prefer to employ one or more continuous sealing members 30 carried incontinuous channels 31' that encompass the opening in the front of the chamber 10. In the case illustrated there are inner and outer sealing members 30 of somewhat yielding material carried in the channels 31 and adapted to conform to and seal with the inner surface of the door 11.

The door carrying means B is provided to shiftably carry the door 11 from a' closed position to an open position and is adapted to move the door forwardly and upwardly as will be apparent from an examination of Figs. 4 and 5 of the drawings. It is a feature of the present invention that the entire door is'moved forwardly away from the face 27 and the sealing members 30 before it is moved upwardly to the position shown in Fig. 5 of the drawings. The means B involves, generally, a pair of spaced arms 33 that are pivotally supported on the frame A and which are adapted to swing between the position shown in Figs. 4 and 5, and a torsion bar 34 that extends between the arms 33 so that the arms move in unison. The arms 33 are alike and parallel with each other, and joined to the terminal ends of the bar 34 at the upper end portions 35 of the arms and are provided with door carrying fittings 36 at their lower terminal ends. The fittings 36 are in the nature of'journals and pivotally carry the door 11 through suitable brackets 37 so that the door is balanced on a substantially neutral axis. That is, the door 11 is carried on'a horizontal axis at or about the center of balance of the door: It is-to be understood that the present invention may be embodied in a mechanism that occurs at one side of the door only.

The torsion bar 34 is provided to connect the arms 33 so that they operate together and is preferably a simple shaft-like member rotatably supported at one side of the chamber in journals 38 carried by'the header 26 or rearwardly extending members 27 of the frame A, or both. As shown, there is a plurality of journals 38 in axial alignment with each other androtatably carrying the bar 34 at the upper side of the chamber 10.

The door guiding means 0 is provided to control movement of the door 11 asit is moved forwardly and up wardly and includes a track 40 at each sideof the door 11, which tracks are carried by the vertical frame members 25. The tracks 40 are opposed to and parallel with each other and each is an elongate vertically disposed element secured to the member to form an inwardly facing channel 41, there being a channel 41 at each side of the structure facingthe' outer edge of the door. In practice, the channels 41 extend from the top of the opening in the chamber 10 to a point somewhat below the bottom of the opening in the chamber 10.

Also included in the door guiding means C is a pair of followers, preferably in the form of guide rollers 42 that operate in the channels 41 to control the movement of the door 11. As shown, the rollers 42 are carried on pinions 43 that project from the lower end of the door 11 at the sides thereof so that the rollers 42 are laterally spaced from the sides of the door and are operable in the channels 41. The pinions 43 are on a common axis, preferably an axis below the lower edge of the door 11.

As will be apparent from the structure thus far described, the door 11 is controlled by the rollers 42 that track in the channels 41 when the door is raised or lowered. In practice, there may be a stop 44 at the upper end of the channel 41 to limit upward travel of the rollers 42 in the channels 41.

The door operating means D may be provided to actuate the mechanism of the present invention and may vary widely as circumstances require. As shown, the means D is preferably a fluid operated means in which case it may involve one or more cylinder and piston units 50, preferably one unit at each side of the structure adapted'to move or shift the arms 33 thereof. It will be readily apparent that various types of operating means may be employed, for example, a motor and chain wheel drive. As shown, the units are alike and each has a cylinder 51 pivotally anchored to a brace 28 of the frame A at 52 and has a piston and rod 53 pivotally connected to the arms 33 at 54. The anchor point 52 is well below the journals 38 above described, so that the arms 33 are operated or shifted forwardly and then upwardly between the positions shown in Figs. 4 and 5 of the drawings, when the units 50 are operated.

In order to allow for forward movement of the door 11 before vertical movement thereof, the channels 41 formed by the track 40 are substantially wider than the diameter of the rollers 42. Therefore, the door 11 is allowed to shift or move forwardly and substantially horizontally before the rollers 42 begin to move or progress upwardly in the channels. Because the door 11 is carried by the outer ends of pivotally mounted swinging arms 33 that depend substantially vertically when in the closed position, the door is moved or shifted in a wide are so that practically speaking it is moved horizontally away from the seals 30.

In order to actuate the cylinder and piston units 50 there is a source of fluid under pressure that is supplied to a control valve 55 through a supply line 56. The valve 55 may be any suitable four-way valve, preferably under control of a lever 57. A fluid connection or line 58 extends from the valve 55 to the rear end of the cylinders 51 while a fluid connection or line 59 extends from the valve 55 to the forward end of the cylinders 51. In practice, the lines 58 and 59 are pipe or tubing and suitable flexible hose connections 60 and 61 join with the rear and forward heads of the cylinders 51, respectively. When fluid is fed under pressure to the line 58 and hoses 60, the units 50 act to raise or lift the arms 33 and door 11 and when fluid is fed under pressure to the lines 59 and hoses 61, the units 50 act to loweror drop the arms 33 and door 11. A drain line 62 is provided to exhaust fluid after it has been used in the piston units 50.

The door balancing means E is provided to counteract the weight of the door 11 and the other elements of the mechanism that I have provided, and involves a counterbalance 65 carried by extensions 66 of the arms 33. It is to be observed that the counter-balance 65 is carried by the extensions 66 at a point diametrically opposite the fittings 36 that pivotally carry the door 11, as shown. The extensions 66 are in effect continuations of the arms 33 and project upwardly from the arms 33 when the arms are in the position shown in Fig. 5 of the drawings. It will be readily understood that the counterbalance 65 may be of suitable weight so that little force is necessary in order to move or operate the mechanism. Further, it will be apparent that the arms 33 and extensions 66 move together so that action of the counterbalance is uniform or constant at the fittings 36.

From the foregoing and from the various positions of the door as illustrated in Fig. 4 of the drawings, it will be apparent that I have provided an. extremely effective mechanism for handling a door or closure of the character under consideration. After the door is moved or shifted horizontally from the front of the chamber 16 it is lifted upwardly and out of the way so that the floor area in front of the. chamber 10 is not encumbered in any way. In fact, with the mechanism that I have provided the door does not pass through or by the floor area in front of the chamber, but is lifted and is progressively shifted upwardly and outwardly where it is held or suspended in a substantially horizontal position. It will also be apparent that as the door 11 is initially moved away from the front of the chamber the sealing engagement is broken by said horizontal movement after which the door is lifted. Further, the mechanism that I have provided is balanced and may be manually operated if desired without the aid of the operating means D.

Having described on a typical preferred form and application of my invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art and fall within the scope of the following claims.

Having described my invention, I claim:

1. In a door mechanism adapted to open and close a planar door opening, a door panel, a pair of elongated guide tracks respectively paralleling the plane of the opening, a laterally projecting guide element at each of two laterally opposed corners of said door freely engaging said tracks, respectively, an actuating lever arm pivoted to a fixed fulcrum located outside the confines of said opening, means pivoting one end of said arm to the door at substantially the point of balance thereof, and a counterbalance engaged with said arm so that the arm supports said door, actuation of said arm moving said door from its closed position to its open position with the engagement of said guide elements in said guide tracks guiding the said two laterally opposed corners of the door linearly in the plane of the opening door during door movement.

2. In a door mechanism adapted to open and close a vertical opening in a supporting structure, such as a furnace or the like, a door, a pair of vertically elongated guide tracks disposed on opposing sides of said opening, a laterally projecting guide element at each of the lower corners of said door and freely engaging said tracks, respectively, for movement therealong, means on said structure defining a fulcrum generally superimposed over said opening and displaced from the vertical plane of the door, an elongated lever arm pivoted on said 6 fulcrum, means pivoting the depending end of said arm to said door at substantially the center of balance thereof, and a counterbalance engaged with said arm so that the arm supports said door, actuation of said arm moving the upper extremity of said door arcuately upwardly and outwardly from the opening and moving the lower extremity of said door linearly vertically along a path defined by said tracks.

3. In a door mechanism adapted to open and close a vertical opening in a supporting structure, such as a furnace or the like, a door, a pair of vertically elongated guide tracks disposed on opposing sides of said opening, a laterally projecting guide element at each of the lower corners of said door and freely engaging said tracks, respectively, for movement therealong, means on said structure defining a fulcrum generally superimposed over said opening and displaced from the vertical plane of the door, an elongated lever arm pivoted on said fulcrum, means pivoting the depending end of said arm to said door at substantially the center of balance thereof, a counterbalance engaged with said arm so that the arm supports said door, and a fluid pressure actuated piston and cylinder assembly for actuating said arm, said assembly acting on said arm intermediate said fulcrum and said point of connection of said arm and said door, actuation of said arm moving the upper extremity of said door arcuately upwardly and outwardly from the opening and moving the lower extremity of said door linearly vertically along a path defined by said tracks.

References Cited in the file of this patent UNITED STATES PATENTS 693,952 Cross Feb. 25, 1902 812,728 Deppe Feb. 13, 1906 1,215,418 Selleck Feb. 13, 1917 1,275,591 Ogden et al Aug. 13, 1918 2,533,423 Bunch Dec. 12, 1950 2,555,204 Sorrell May 29, 1951 

